4种禾草种子发芽条件的筛选研究

针对马唐(Digitaria sanguinalis(L.)Scop)、止血马唐(Digitaria ischaemum(Schreib.)Schreib.)、细弱隐子草(Cleistogenes gracilis Keng)和糙隐子草(Cleistogenes squarrosa(Trin.)Keng)4种禾本科牧草种子发芽率低的现象,使用不同温度、不同浓度KNO3溶液和预冷等处理对其进行打破休眠和促进萌发的研究,并对供试种子的适宜发芽条件进行筛选。结果表明:马唐种子不存在休眠问题,预冷和KNO3溶液对促进其萌发均没有显著效果;止血马唐种子存在休眠且生活力偏低,预冷能够打破休眠,KNO3处理能够有效提高其种子的生活力(P0.05);细弱隐子草和糙隐子草发芽率低主要原因是种子生活力低,KNO3处理能够极显著提高种子的生活力和发芽率(P0.01)。4种种子的最适发芽条件分别是:马唐种子用KNO3(0.2%)处理或不处理,在30℃恒温发芽;止血马唐、细弱隐子草和糙隐子草种子均为用KNO3(0.2%)处理并预冷(7d)后20～30℃变温发芽。

Seed Germination Conditions of Four Grass Forages Species

Different methods(temperatures,KNO3 solutions and pre-cooling treatments)were investigated to break the dormancy and promote seed germination of: Digitaria sanguinalis(L.)Scop,Digitaria ischaemum(Schreib.) Schreib,Cleistogenes gracilis Keng and Cleistogenes squarrosa(Trin.) Keng.Results indicated that Digitaria sanguinalis seeds had no dormancy and both pre-cooling and KNO3 solution did not significantly promote germination.Digitaria ischaemum seeds had both dormancy and low-viability;pre-cooling treatment could break the dormancy effectively and KNO3 solution could effectively improve viability.The low seed germination percentage of Cleistogenes gracilis and Cleistogenes squarrosa was enhanced with a KNO3 solution improving both seed viability and seed germination percentage.Optimum seed germination conditions were: Digitaria sanguinalis seed germinated at 30℃ with or without KNO3(0.2%)solution treatment;Digilaria lschaemum,Cleistogenes gracilis and Cleistogenes spuarrosa seeds germinated at 20~30℃ with KNO3(0.2%)solution and pre-cooling treatment(7 d).